Over the last 65 years, returns on assets have decreased about 75 percent; indicative, says Deloitte Center for the Edge Independent Co-Chairman John Seely Brown, that the old guard of doing business is no longer viable. Whereas companies used to be guaranteed longevity if they made it into the S&P 500, nowadays many survive there only five or ten years. The 21st century is qualitatively different, says Seely Brown, with new technological institutional mechanisms forcing new business practices.